Plugin changes modeling behavior regarding event-based gateway

[hkupitz]

Describe the Bug

The plugin seemingly changes the modeling behavior regarding the event-based gateway. As per the BPMN 2.0 specification targets of an event-based gateway must not have any other incoming sequence flows.

With a clean Modeler install, when connecting a second sequence flow to such an event, the already connected incoming sequence flow per default is deleted automatically:

When the plugin is installed this doesn't happen, allowing two incoming sequence flows to be connected to the event:

Steps to Reproduce

1. Open test diagram
2. Connect the event-based gateway to the intermediate message catch event again.
3. See that the now illegal other flow to the catch event remains in place.

Expected Behavior

The incoming sequence flow that is already connected to the event following the event-based gateway should be removed when connecting a second element.

Environment

• OS: Windows 10
• Modeler version: 4.11.1
• Plugin version: 0.14

[nikku]

Thanks for opening this issue.

Please always share the diagram you were able to reproduce a bug with.

I can reproduce the issue on the bpmn.io demo using this test diagram. Because of that I suspect that it is a regression in a recent bpmn-js release, not a bug in the token-simulation.